I was at a friends house and noticed some large bottle jacks he said he no longer used. When I went to lift one to check it out, it was really relatively light weight and appeared to be made of aluminum. He said they were air jacks rated at 20 ton. Does anyone have experience with something similar?

These are pictures of one of the jacks. The name is worn off, so I haven't been able to find anything online about them. He says they are hydraulic/air and rated at 20 tons, but I suspect they are pneumatic since I can't find any port for fluid. Also, the pistons are hollow, so I question whether they are really good for 20 ton. When hooked up, the two of them can be operated simultaneously be one foot pedal for up and down. Any clues?

I have a set of those that came with an alignment machine. They are air operated and mine have a valve for each jack. Great for quick lifts setting up the alignment equipment and they are easy to handle in the pit; about 8 or 10 pounds.

Lee, that makes perfect sense since they are a pair and were both controlled with one foot peddle. Do you know who the manufacturer is and what the lift rating is. I don't think they are near the 20 tons he thinks they are.

Aren't those the old 4,000#(2000#ea) jacks from a Hunter alignment machine from the 60's before they went to the swing out jacks ? I remember using those if you didn't pin those they leaked off big time and you had to start over

That could be it. I have no knowledge of the Hunter alignment system, but these have to be pinned to stay up. I guess there is no free lunch here; you don't get a 20 ton jack that only weighs 10 pounds.